feat: P2.2 Create Appointment from Email + P2.4 Calendar Dashlet + P2.12 Action Wheel + P2.14 Share Files

- P2.2: 'Create Appointment' button in email viewer → pre-fills event modal
  with subject, body, participants, date. calendar-store newEventPrefill state.
- P2.4: MiniCalendarDashlet in sidebar bottom — month grid with event dots,
  day click navigates to calendar. Collapsible, respect firstDayOfWeek.
- P2.12: Custom radial menu (components/ui/radial-menu.tsx) — circular SVG
  menu with keyboard nav, animations. Wired into email-list, contact-list,
  file-browser, calendar-month-view right-click handlers.
- P2.14: 'Send as Attachment' button in file browser — opens compose tab
  with selected files pre-attached via Pro tab store.

components/calendar/event-modal.tsx

@@ -49,6 +49,10 @@ interface EventModalProps {
   onPreviewChange?: (preview: PendingEventPreview | null) => void;
   currentUserEmails?: string[];
   isMobile?: boolean;
+  prefillTitle?: string;
+  prefillDescription?: string;
+  prefillParticipants?: { name?: string; email: string }[];
+  prefillDate?: string;
 }
 
 function formatDateInput(d: Date): string {
@@ -178,6 +182,10 @@ export function EventModal({
   onPreviewChange,
   currentUserEmails = [],
   isMobile = false,
+  prefillTitle,
+  prefillDescription,
+  prefillParticipants,
+  prefillDate,
 }: EventModalProps) {
   const t = useTranslations("calendar");
   const locale = useLocale();
@@ -228,6 +236,10 @@ export function EventModal({
       d.setHours(now.getHours() + 1, 0, 0, 0);
       return d;
     }
+    if (prefillDate) {
+      const d = new Date(prefillDate);
+      if (!isNaN(d.getTime())) return d;
+    }
     const d = new Date();
     d.setHours(d.getHours() + 1, 0, 0, 0);
     return d;
@@ -244,8 +256,8 @@ export function EventModal({
     return addHours(getInitialStart(), 1);
   };
 
-  const [title, setTitle] = useState(event?.title || "");
-  const [description, setDescription] = useState(event?.description || "");
+  const [title, setTitle] = useState(event?.title || prefillTitle || "");
+  const [description, setDescription] = useState(event?.description || prefillDescription || "");
   const [location, setLocation] = useState(
     event?.locations ? Object.values(event.locations)[0]?.name || "" : ""
   );
@@ -328,7 +340,12 @@ export function EventModal({
   const [isSaving, setIsSaving] = useState(false);
 
   const [attendees, setAttendees] = useState<{ name: string; email: string }[]>(() => {
-    if (!event?.participants) return [];
+    if (!event?.participants) {
+      if (prefillParticipants && prefillParticipants.length > 0) {
+        return prefillParticipants.map(p => ({ name: p.name || "", email: p.email }));
+      }
+      return [];
+    }
     return existingParticipants
       .filter(p => !p.isOrganizer)
       .map(p => ({ name: p.name, email: p.email }));